First-Principles Calculations of the Electronic Structure and Optical Properties of Yttrium-Doped ZnO Monolayer with Vacancy

The electronic structures and optical characteristics of yttrium (Y)-doped ZnO monolayers (MLs) with vacancy (zinc vacancy, oxygen vacancy) were investigated by the first-principles density functional theory. Calculations were performed with the GGA+U (generalized gradient approximation plus U) approach, which can accurately estimate the energy of strong correlation semiconductors. The results show that the formation energy values of Y-doped ZnO MLs with zinc or oxygen vacancy (VZn, VO) are positive, implying that the systems are unstable. The bandgap of Y-VZn-ZnO was 3.23 eV, whereas that of Y-VO-ZnO was 2.24 eV, which are smaller than the bandgaps of pure ZnO ML and Y-doped ZnO MLs with or without VO. Impurity levels appeared in the forbidden band of ZnO MLs with Y and vacancy. Furthermore, Y-VZn-ZnO will result in a red-shift of the absorption edge. Compared with the pure ZnO ML, ZnO MLs with one defect (Y, VZn or VO), and Y-VZn-ZnO, the absorption coefficient of Y-VO-ZnO was significantly enhanced in the visible light region. These findings demonstrate that Y-VO-ZnO would have great application potential in photocatalysis.

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First-Principles Study on Co-Doped ZnO with Oxygen Vacancy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.154-155.124 ◽

2010 ◽

Vol 154-155 ◽

pp. 124-129

Author(s):

Zhen Zhen Weng ◽

Zhi Gao Huang ◽

Wen Xiong Lin

Keyword(s):

Oxygen Vacancy ◽

First Principles ◽

Density Functional ◽

Exchange Interactions ◽

First Principles Calculations ◽

Functional Theory ◽

Ferromagnetic Exchange ◽

Ferromagnetic Ground State ◽

Doped Zno ◽

Co Doped

The interatomic exchange interactions and the electronic structure of Co-doped ZnO with and without oxygen vacancy have been investigated by the first-principles calculations based on density functional theory. It is found that the oxygen vacancy can strengthen the ferromagnetic exchange interaction between Co atoms and might be available for carrier mediation. The oxygen vacancy near to the Co atoms is more favorable for the ferromagnetic ground state.

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Probing the electronic structures of Con (n = 1–5) clusters on γ-Al2O3 surfaces using first-principles calculations

Physical Chemistry Chemical Physics ◽

10.1039/c6cp06785a ◽

2017 ◽

Vol 19 (5) ◽

pp. 3679-3687 ◽

Cited By ~ 10

Author(s):

Tao Yang ◽

Masahiro Ehara

Keyword(s):

Density Functional Theory ◽

First Principles ◽

Electronic Structures ◽

Density Functional ◽

Density Functional Theory Calculations ◽

First Principles Calculations ◽

Functional Theory

Using density functional theory calculations, we discussed the geometric and electronic structures and nucleation of small Co clusters on γ-Al2O3(100) and γ-Al2O3(110) surfaces.

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Electronic structure of cubic BaTbO3 from first-principles pseudopotential calculations

Canadian Journal of Physics ◽

10.1139/p06-008 ◽

2006 ◽

Vol 84 (2) ◽

pp. 115-120 ◽

Cited By ~ 3

Author(s):

G Y Gao ◽

K L Yao ◽

Z L Liu

Keyword(s):

Electronic Structure ◽

First Principles ◽

Density Functional ◽

First Principles Calculations ◽

Generalized Gradient ◽

Functional Theory ◽

Exchange Correlation ◽

Pseudopotential Calculations ◽

Correlation Potential ◽

Density Contour

First-principles calculations of the electronic structure are performed for cubic BaTbO3 using the plane-wave pseudopotential method within the framework of density functional theory and using the generalized gradient approximation for the exchange-correlation potential. Our calculations show that cubic BaTbO3 is metallic, and that this metallic character is mainly governed by the Tb 4f electrons and the hybridization between the Tb 5d and O 2p states. From the analysis of the density of states, band structure, and charge density contour, we find that the chemical bonding between Tb and O is covalent while that between Ba and TbO3 is ionic. PACS Nos.: 71.15.Mb, 71.20.-b

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Oxygen Vacancy Induced Magnetism in Anti-Perovskite Topological Dirac Semimetal Ba3SnO

Physical Chemistry Chemical Physics ◽

10.1039/d1cp03989j ◽

2021 ◽

Author(s):

Javaria Batool ◽

Syed Muhammad Alay-e-Abbas ◽

Gustav Johansson ◽

Waqas Zulfiqar ◽

Muhammad Arsam Danish ◽

...

Keyword(s):

Density Functional Theory ◽

Oxygen Vacancy ◽

Electronic Properties ◽

Thermodynamic Stability ◽

First Principles ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Vacancy Defect ◽

Functional Theory ◽

Dirac Semimetal

The thermodynamic, structural, magnetic and electronic properties of pristine and intrinsic vacancy defect containing topological Dirac semimetal Ba3SnO are studied using first-principles density functional theory calculations. The thermodynamic stability of...

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Unexpected superhard phases of niobium triborides: first-principles calculations

RSC Advances ◽

10.1039/c6ra05162f ◽

2016 ◽

Vol 6 (54) ◽

pp. 49214-49220 ◽

Cited By ~ 3

Author(s):

Xiaofeng Li ◽

Junyi Du

Keyword(s):

Density Functional Theory ◽

First Principles ◽

Density Functional ◽

High Pressures ◽

Density Functional Theory Calculations ◽

Search Method ◽

First Principles Calculations ◽

Functional Theory ◽

Swarm Optimization ◽

Structure Search

Using an unbiased structure search method based on particle-swarm optimization algorithms in combination with density functional theory calculations, we investigate the phase stability and electronic properties of NbB3 under high pressures.

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Composition-Dependent Basics of Smart Heusler Materials from First- Principles Calculations

Materials Science Forum ◽

10.4028/www.scientific.net/msf.684.1 ◽

2011 ◽

Vol 684 ◽

pp. 1-29 ◽

Cited By ~ 27

Author(s):

Peter Entel ◽

Antje Dannenberg ◽

Mario Siewert ◽

Heike C. Herper ◽

Markus E. Gruner ◽

...

Keyword(s):

Shape Memory ◽

First Principles ◽

Density Functional ◽

Elevated Temperatures ◽

Heusler Alloys ◽

Density Functional Theory Calculations ◽

First Principles Calculations ◽

Magnetic Shape Memory ◽

Functional Theory ◽

Magnetic Shape Memory Alloy

The structural and magnetic order are the decisive elements which vastly determine the properties of smart ternary intermetallics such as X2YZ Heusler alloys. Here, X and Y are transition metal elements and Z is an element from the III-V group. In order to give a precise prescription of the possibilities to optimize the magnetic shape memory and magnetocaloric effects of these alloys, we use density functional theory calculations. In particular, we outline how one may find new intermetallics which show higher Curie and martensite transformation temperatures when compared with the prototypical magnetic shape-memory alloy Ni2MnGa. Higher operation temperatures are needed for technological applications at elevated temperatures.

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Barrier to Migration of the Intrinsic Defects in Silicon in Different Charged System Using First-principles Calculations

MRS Proceedings ◽

10.1557/proc-864-e9.17 ◽

2005 ◽

Vol 864 ◽

Cited By ~ 1

Author(s):

Jinyu Zhang

Keyword(s):

Density Functional Theory ◽

First Principles ◽

Density Functional ◽

First Principles Calculations ◽

Generalized Gradient ◽

Functional Theory ◽

Diffusion Behavior ◽

Generalized Gradient Approximation ◽

Charged System ◽

And Diffusion

AbstractUsing density functional theory (DFT) calculations within the generalized gradient approximation (GGA), we have investigated the structure, energies and diffusion behavior of Si defects including interstitial, vacancy, FFCD and divacancy in various charged states.

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FIRST-PRINCIPLES STUDY OF ADSORPTION OF CN ON Cu(111)

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633607003167 ◽

2007 ◽

Vol 06 (03) ◽

pp. 523-529 ◽

Cited By ~ 3

Author(s):

WENZHEN LAI ◽

HONG RAN ◽

DAIQIAN XIE

Keyword(s):

First Principles ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Stationary Points ◽

Plane Wave Expansion ◽

Generalized Gradient ◽

Functional Theory ◽

Adsorption Sites ◽

Parallel Mode ◽

Pseudo Potential

The adsorption of CN on Cu (111) has been investigated using density functional theory calculations based on plane-wave expansion and pseudo-potential treatment. Calculations within the generalized gradient approximation predicted a preference for CN in the fcc C -down site. No stationary points corresponding to pure parallel mode were found. But the tilted mode was found to be achievable. The calculated vibrational frequencies of CN were used to correctly discriminate between the adsorption sites.

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Quantum-chemical study of nitrogen and magnesium co-doping in α-Cr2O3

Modern Physics Letters B ◽

10.1142/s0217984916502195 ◽

2016 ◽

Vol 30 (14) ◽

pp. 1650219

Author(s):

Soraya Jácome ◽

Arvids Stashans

Keyword(s):

First Principles ◽

Density Functional ◽

Quantum Chemical Study ◽

Chemical Study ◽

First Principles Calculations ◽

Generalized Gradient ◽

Functional Theory ◽

Text Type ◽

Co Doping ◽

The Density Functional Theory

Study of corundum-type chromium oxide ([Formula: see text]-Cr2O3) crystal doped with the nitrogen and magnesium impurities has been carried out through the use of first-principles calculations based on the density functional theory (DFT) and generalized gradient approximation (GGA). Three cases corresponding different impurity–impurity distances have been considered. Structural, electronic and magnetic properties have been studied for all co-doping cases. The [Formula: see text]-type electrical conductivity was found when distance between the Mg and N atoms is equal to 4.10 Å. The results obtained are consistent with the available experimental data.

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Electronic structure and elastic properties of AgZn under pressure from first-principles calculations

Canadian Journal of Physics ◽

10.1139/cjp-2015-0684 ◽

2016 ◽

Vol 94 (3) ◽

pp. 328-333

Author(s):

Yasemin Ö. Çiftci

Keyword(s):

Density Of States ◽

First Principles ◽

Density Functional ◽

Elastic Stiffness ◽

Distribution Analysis ◽

First Principles Calculations ◽

Generalized Gradient ◽

Functional Theory ◽

B2 Structure ◽

Bonding Characteristic

In this study, the structural, elastic, electronic, and bonding nature of AgZn in B2 structure under pressure have been investigated by performing first principles calculations using density functional theory. The exchange-correlation potentials were treated within the generalized gradient approximation. The calculated quantities agree well with the available results. The electronic properties, such as band structure and density of states reveal that AgZn is metallic in nature with a large overlap at the Fermi level. The single-crystal elastic stiffness constants of AgZn are investigated using the stress–strain method. Present results for elastic constants show that AgZn is mechanically stable. The chemical bonding is interpreted by calculating the density of states and electron density distribution analysis. AgZn has ionic bonding characteristic.

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